Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (8): 818-833.DOI: 10.17521/cjpe.2020.0373

Special Issue: 植物功能性状

• Research Articles • Previous Articles     Next Articles

Effects of grassland utilization on the functional traits of dominant plants in a temperate typical steppe

ZHANG Jing-Hui1,2,3*, WANG Zheng1*, HUANG Yong-Mei4,**(), CHEN Hui-Ying5, LI Zhi-Yong1,2,3, LIANG Cun-Zhu1,2,3   

  1. 1School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
    2Key Laboratory of Mongolian Plateau Ecology and Resource Utilization, Ministry of Education, Hohhot 010021, China
    3Provincial and Ministry Jointly Build the Cultivation Base of State Key Laboratory of Grassland Ecology, Hohhot 010021, China
    4Faculty of Geographical Science, State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
    5Curriculum and Teaching Materials Research Institute, Peopleʼs Education Press, Beijing 100081, China
  • Received:2020-11-12 Revised:2021-04-02 Online:2021-08-20 Published:2021-04-28
  • Contact: HUANG Yong-Mei
  • Supported by:
    National Key R&D Program of China(2016YFC0500503);National Natural Science Foundation of China(31960243);Natural Science Foundation of Nei Mongol(2018BS03006)

Abstract:

Aims When the external environment changes, plants can change their own functional traits and adjust adaptation strategies in a timely manner. Therefore, plant functional traits can effectively reflect the response of plants to the change of grassland use. However, there are few studies on the effects of grassland use patterns from the perspective of plant functional traits in the Nei Mongol grassland. Therefore, from the perspective of functional traits, this paper reveals the adaptation strategies of plants after external disturbances, aiming to provide basic data support and scientific basis for the sustainable management of natural grasslands.
Methods In this study, four important dominant species of Stipa grandis, Leymus chinensis, Cleistogenes squarrosa and Artemisia frigida in the typical grasslands of Nei Mongol were selected as the research objects to explore the differences in the functional traits of dominant species under the influence of long-term free grazing, mowing, short-term enclosed and long-term reservation.
Important findings We found that: 1) Vegetation height, root length and carbon and nitrogen concentration of dominant plants in Nei Mongol typical grasslands are reduced under long-term grazing. Changes in these traits can miniaturize individual plants and reduce their palatability, indicating that plants may adopt avoiding grazing strategy to adjust to the interference of long-term free grazing. Under the mowing management, the vegetation height and specific leaf area of the dominant species tend to increase. Among them, the nitrogen content of A. frigida is the most sensitive to the response of mowing. The nitrogen concentration in its roots, stems, leaves are the lowest in the mowing sites; the carbon and nitrogen concentration of plants increases under enclosure and long-term non-disturbance treatments, indicating that the plant transforms from resource acquisition strategy to resource storage strategy through changes in functional traits when the disturbance intensity is reduced. 2) The analysis of the assemblage of functional traits of dominant species shows that C. squarrosa has a small plant height and a high specific leaf area, and A. frigida has a high lignin and nitrogen concentration. The two species thus can adopt some avoidance (escaping from grazers) and tolerance (regrowth capacity after defoliation) strategies to improve their grazing resistance; S. grandis has the highest plant height, the largest leaf dry matter concentration, the highest stem and leaf cellulose concentration, which indicates that S. grandis is a very typical competitive species. Under management conditions with low interference intensity, the competitive pressure of S. grandis (Competitive strategy) against other species may be an important reason for its high dominance.

Key words: plant functional traits, grassland utilization patterns, typical grasslands, dominant species, element traits